| Author | Message | ||
     Xodot |
'08 1125R only mod is E B R ECM track day 100 degrees in the shade engine temp at end of session = 221 F (105C) came into pit, shut engine off and about a cup (250ml) puked out the overflow line. rad overflow container found to be empty topped up the rad overflow container to the line, went for another session and same puking when engine shut off Did NOT top off, went for another session, came in and let engine run until coolant temp dropped few degrees, shut engine off - no more vomit of rad fluid for the rest of a very hot day. What causes the vomiting? Heat stroke of a Rotax nature??? <wink> | ||
| Jdugger |
So, there's an 'ideal' amount of water to have in the radiator at a given temperature. If your bike is run in the hot summer, having the system tightly bled and the water topped off, there's a 100% chance it will need to get rid of some of that water at high temps. That's the puking. If you look at the rad cap you will notice it has a spring valve that bleeds to the overflow under enough pressure. If you let your bike cool completely and then pop the rad cap and take a look after a hot track day, you will be nothing short of shocked at how low the water level is. Just let the bike warm up to close to operating temps (say 180-190) in the pits before you really get on it and you will never have an issue. Come winter, top off the coolant. On my race bike, the coolant catch bottle is effectively "total loss". That is, once it leaves the rads, it's dumped into a catch bottle and I just empty the bottle. The first few times I ride hard in the heat after bleeding the coolant system I get some water in the catch bottles. On going, it's fine. What ** REALLY ** sucks is when your bike overheats on the grid and goes into skip-spark for the start. You go lugging down the front straight behind the grid until the bike gets enough air to cool off, then have to make a bunch of passes just to get back in the race. | ||
| Sl33py |
school me here, but shouldn't the overflow (puke) have gone into the empty overflow bottle before dumping out? and if it overflowed the overflow bottle - there would be some in the bottle right? just confused how the bike puked with an empty overflow bottle... | ||
| Xodot |
SI33py - the amount of fluid that left the rad system seems to have come from the overflow tank. I say that because it seemed I put in roughly as much had been dumped on the ground. I "think" the meat here is Jdugger saying: "there's an 'ideal' amount of water to have in the radiator at a given temperature" I topped off the rad in the cool of spring time filling the stock overflow tank appropriately. In the extreme heat - that amount became "too much" and system purged itself to an appropriate level. I do not understand how the sudden release of water came about however. Since the bike was running hot on the track, why the sudden expulsion the instant the engine was shut off? | ||
| Jdugger |
> why the sudden expulsion the instant the engine was shut off? Heat/temp rises in the motor, sometimes dramatically, when it's first shut off. I have to keep a fan on mine in the paddock. | ||
| Sl33py |
xo and Jdugger - thanks! sounds like heat soak - my old landcruiser always shows hot when i shut off and then a few minutes later back on. until the cooling flows again and it drops quickly. big iron block really shows it... I thought the stock fans keep going for a bit after shutdown to help with this? Does the EBr ECM not have this feature? | ||
| Xodot |
I thought the stock fans keep going for a bit after shutdown to help with this? Does the EBr ECM not have this feature? yes they do, but with no coolant circulating through the engine I guess it's just not enough X | ||
| Jdugger |
> I thought the stock fans keep going for a bit after shutdown to help with this? A bit. Remember, though, water is no longer circulating, so you are basically cooling the water in the radiators without cooling the water in the motor. To my knowledge, this is universal among all water cooled motors. |
